The echocardiographer and the diagnosis of patent foramen ovale.

PFO is diagnosed by echocardiography using the combination of transthoracic two-dimensional imaging of the interatrial septum, followed by color and spectral Doppler (and if necessary saline contrast) imaging. Transesophageal imaging is an important adjunct when transthoracic imaging is not conclusive or yields suboptimal images.Three-dimensional echocardiography is useful for defining fenestrations within a PFO.